The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 27, 2003
Filed:
Jun. 20, 2001
Applicant:
Inventors:
Assignee:
Ricoh Company, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H02K 2/900 ;
U.S. Cl.
CPC ...
H02K 2/900 ;
Abstract
A direct current motor rotation detecting apparatus and a direct current motor rotation control apparatus detect and control at least one of a rotational direction, a rotational speed, a rotational position, and a cumulative rotation number of a rotor of a direct current motor. The apparatus include at least one rotation detecting brush which detects a rotation of the rotor, a differentiating circuit which differentiates a voltage obtained through the at least one rotation detecting brush, and a pulse generator triggered by the differentiating circuit at a time interval proportional to a rotational speed of the direct current motor to generate pulses having a predetermined pulse width.